mannich-bases and 1-1-diphenyl-2-picrylhydrazyl

The search for antibacterial agents for the combat of nosocomial infections is a timely problem, as antibiotic-resistant bacteria continue to thrive. The effect of indoline substituents on the antibacterial properties of aminoalkylphenols was studied, leading to the development of a library of compounds with minimum inhibitory concentrations (MICs) as low as 1.18 μM. Two novel aminoalkylphenols were identified as particularly promising, after MIC and minimum bactericidal concentrations (MBC) determination against a panel of reference strain Gram-positive bacteria, and further confirmed against 40 clinical isolates (Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Enterococcus faecium, and Listeria monocytogenes). The same two aminoalkylphenols displayed low toxicity against two in vivo models (Artemia salina brine shrimp and Saccharomyces cerevisiae). The in vitro cytotoxicity evaluation (on human keratinocytes and human embryonic lung fibroblast cell lines) of the same compounds was also carried out. They demonstrated a particularly toxic effect on the fibroblast cell lines, with IC

Topics: Animals; Anti-Bacterial Agents; Antioxidants; Artemia; Biphenyl Compounds; Cell Line; Cell Survival; Dose-Response Relationship, Drug; Gram-Positive Bacteria; Humans; Indoles; Mannich Bases; Microbial Sensitivity Tests; Molecular Structure; Phenols; Picrates; Structure-Activity Relationship

The biological importance of antioxidants influenced to synthesize some curcumin-related compounds as potential antioxidants. Accordingly, a series of 2,4-diaryl-3-azabicyco[3.3.1]nonan-9-ones were synthesized with polyphenolic and/or polymethoxyphenyl groups by modified Mannich condensations. The yield was significantly improved using BF(3)·SiO(2) as heterogeneous catalyst under mild conditions. Stereochemistry of all the synthesized compounds was established as twin-chair with an equatorial disposition of the aryl groups, through their NMR and XRD interpretations. The ABNs 8 (curcumin analog) and 10 (bis-demethoxycurcumin analog) showed an effective profile over curcumin, α-tocopherol, and vitamin C by chemical methods. Further, the efficiency of one of the active molecules, ABN 10, was demonstrated by its intracellular ROS inhibition activity on RAW 264.7 macrophage cells by FACS analysis in dose-dependent manner.

Topics: alpha-Tocopherol; Animals; Antioxidants; Ascorbic Acid; Biphenyl Compounds; Boranes; Catalysis; Cell Line; Curcumin; Macrophages; Mannich Bases; Mice; Models, Molecular; Oxidation-Reduction; Picrates; Reactive Oxygen Species; Silicon Dioxide

Chalcones and Mannich bases have been reported to present antiinflammatory activities as well as inhibitory activities on several factors implicated in inflammation disorders. A series of chalcones and some related Mannich bases were prepared by Claisen-Schmidt condensation of appropriate acetophenones with appropriate aromatic aldehyde. Mannich bases were derived from chalcones, with formaldehyde and the corresponding amine. The compounds were tested in vitro for their ability to inhibit various enzymes involved in the arachidonic acid cascade, for their antioxidant behaviour and in vivo for anti-inflammatory activity. Some chalcones and Mannich bases present strong anti-inflammatory and antioxidant activities. Almost all the tested compounds present high inhibitory activity on lipid peroxidation. Some compounds showed potent inhibitory effect on superoxide anion formation. Among the tested compounds 5 and 6 showed the highest lipoxygenase (LO) inhibitory activity. All the tested compounds inhibit both the proteolytic and esteratic activities of trypsin and chymotrypsin. The results indicated that the anti-inflammatory effects of the compounds were partially mediated, through their antioxidant activity. Attempts to correlate quantitatively structure with activity revealed that lipophilicity and molar refractivity influence the biological response.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Biphenyl Compounds; Carrageenan; Chalcones; Chymotrypsin; Edema; Esterases; Free Radical Scavengers; Glutathione; Heme; Indicators and Reagents; Lipids; Magnetic Resonance Spectroscopy; Mannich Bases; Picrates; Reactive Oxygen Species; Spectroscopy, Fourier Transform Infrared; Superoxides